Oil field operators drill boreholes into subsurface reservoirs to recover oil and other hydrocarbons. If the reservoir has been partially drained or if the oil is particularly viscous, the oil field operators will often stimulate the reservoir, e.g., by injecting water or other fluids into the reservoir via secondary wells to encourage the oil to move to the primary (“production”) wells and thence to the surface. Other stimulation treatments include fracturing (creating fractures in the subsurface formation to promote fluid flow) and acidizing (enlarging pores in the formation to promote fluid flow).
This flooding process can be tailored with varying fluid mixtures, flow rates/pressures, and injection sites, but may nevertheless be difficult to control due to inhomogeneity in the structure of the subsurface formations. The fluid interface between the reservoir fluid and the injected fluid, often termed the “flood front”, develops protrusions and irregularities that may reach the production well before the bulk of the residual oil has been flushed from the reservoir. This “breakthrough” of the flood fluid is undesirable, as it typically necessitates increased fluid handling due to the injected fluid's dilution of the oil and may further reduce the drive pressure on the oil. Continued operation of the well often becomes commercially infeasible.
The stimulation processes can be tailored with varying fluid mixtures, flow rates/pressures, and injection sites, but may nevertheless be difficult to control due to inhomogeneity in the structure of the subsurface formations. The production process for the desired hydrocarbons also has various parameters that can be tailored to maximize well profitability or some other measure of efficiency. Without sufficiently detailed information regarding the effects of stimulation processes on a given reservoir and the availability and source of fluid flows for particular production zones, the operator is sure to miss many opportunities for increased hydrocarbon recovery.
It should be understood, however, that the specific embodiments given in the drawings and detailed description below do not limit the disclosure. On the contrary, they provide the foundation for one of ordinary skill to discern the alternative forms, equivalents, and other modifications that are encompassed in the scope of the appended claims.